Machine for making paper tubes



Aug. H, 1925. 1,549,493v

J. D. LANE MACHINE FOR MAKING PAPER TUBES Filed Aug. 22. 1924 Patented Aug. 11', 1925.

UNITED STATES JOHN D. LANE, 0F ARLINGTON, MASSACHUSETTS.

MACHINE FOR MAKING PAPER TUBES.

Application filed August 22, 1924. Serial No. 733,536.

To all whom it may concern:

Be it known that I, JOHN D. LANE, a citizen of the United States, residing at Arlington, in the county of Middlesex and State of Massachusetts, have invented new and useful Improvements in- Machines for Making Paper Tubes, of which the following is a specification,

This invention relates to means for forming a paper tube by winding a sheet of glue or cement-coated paper on a rotary mandrel.

The object of the invention is to provide improved means adapted to guide the leading end of the paper sheet to the mandrel preparatory to the rolling operation, to con tinuously exert radial inward pressure on the sheet during the rolling operation,'thereby compacting the tube wall on the mandrel, and to relax the said pressure after the completion of the tube.

Of the accompanying drawings forming a part of this specification,

Figure 1 is a top plan view of a portion of a tube-making machine embodying the invention.

Figure 2 is a section on line 22 of Figure 1 and an end view of the parts at the right.

Figures 3 and 4 are views similar to portions of Figure 2, showing different stages of the operation.

Figure 5 is a perspective view showing a portion of the gripper shown by the preceding figures, and elements of the gripper tensioning and relaxing mechanism hereinafter described.

Figure 6 shows in perspective portions of the mandrel and gripper, and an element of the preferred means supporting one end .of the gripper.

The same reference aiarafiers'indicate the same parts in all of the figures.

In the drawings, 12 designates a rotar non-expansible mandrel journalled in suitable bearings not shown, and rotated by any suitable means in the direction indicated by arrow w. The periphery of the mandrel is preferably provided with longitudinal serrations formed to engage a paper sheet 13, and cause the winding of the sheet on the mandrel, and thus convert the sheet into a tube, the sheet being coated with glue or cement.

In carrying out my invention, I provide a resilient gri per 14, preferably rectangular and made 0 thin sheet metal, and gripper- Supporting, tensioning and relaxing mech'- anlsm organized to movably support the inner end of the gripper in close proximity.

to the mandrel and parallel with the axis thereof, and to movably support the outer end of the gripper farther from the mandrel," the arrangement being such that the grip-- per includes a mandrel-embracing portion designated by 1 1 in Figure 6, and a sheetguiding portion designated by 14* in the same figure, the guiding portion being tangential to the embracing portion. Said mechanism includes movable anchoring means engaged with the inner end of the gripper, movable tensioning means engaged with the outer end of the gripper and normally exerting a yielding tension onthe sheet-guiding portion of the gripper to compress or contract the mandrel-embracing portion 1 1*, and means for relaxing the gripper tension at predetermined periods to permit a maximum expansion of the embracing portion.

The preferred embodiments of said anchoring means, tensioning means, and tension-relaxing means, are as next described.

The anchoring mam.

Mounted on a rod or cross bar 16 fixedly supported above and at the rear of the mandrel, are hubs or collars 17 having arms provided with tapering slots 18, the outer ends of the slots being enlarged. Inserted loosely in the inner portions of the slots is a swinging bar or strut 19 the lower edge of which stands in close proximity to one side of the mandrel 12 and is adapted to swing toward and from the periphery of the mandrel. The inner end of the gripper 14 is fixed as by electric welding, brazing or otherwise to the swinging edge portion of the strut 19. The opposite edge of the strut is held in y the slots 18 by the tendency of the embracing portion of the gripper to expand.

, The tensioning and relaxing mearns.

Mounted on a rod or cross bar 21 supported below and at the rear of themandrel by fixed arms 25, is an upwardly pr0jecting bar 22 to which the rear end of the grlpper 14 is fixed as by a screw 23 secured to an car 24 on the bar and entering an orifice ii. the gripper. With the bar 22 and rod 21 are engaged the opposite ends of a biasing spring 26, the tendency of which is to press the bar in the direction of the arrow 3 and thus exert, through the bar, a yielding tension on the gripper, tending to contract the mandrel-embracing portion journalled in fixed bearings (not shown) and rotated in the direction of the arrow 2.

When theprojections 30 are out of contact with the trundle rolls 28 as shown by Figure 3, the rolls bear. on the collars 29, and the biasing spring 26 exerts a maximum tension on the gripper tending to contract the embracing portion thereof on the mandrel When the projections 30- contact with the trundle rolls as shown by Figures 2 and 4, the bar 22'is displaced 1n the direction required to relax the tension on the gripper and permit the expansion of its mandrelembracing portion by the resilience of the material of the gripper.

The leading end of the paper sheet 13 is inserted between the gripper and the mandrel when the embracing portion of the .gnpper 1s expanded as shown by Fi res 2 and 6. The mandrel commences to wind the sheet into a tube just before the maximum pressure of the spring 26 is exerted on the grlpper. As the winding progresses, the embracing portion of the gripper yields to the increasing thickness of the winding, so that during t e winding operation, the gripper exerts a constant radial inward pressure on the winding and presses the convolutlons thereof closely together and the inner convolution closely against the periphery of the mandrel. The rotation of the shaft 31 is so timed that the winding operation is completed while the projections 30 are passing from the position shown by Figure 2 and before the reach the position shown by Figure 4. en the arm 22 is fully displaced as shown by Figure 4, the embracmg portion of the gripper expands out of contact with the completed tube.

In the organized machine, the mandrel is somewhat more than twice as long as the embracing portion of the gripper, and is moved endwise after the completion of each tube to remove the tube from the embrac- 1D portion and permit the winding of anot er tube on the portion of the mandrel within the embracing portion, the endwise movement of-the mandrel being in one direction after the completion of one tube and back to the original position before the next tube is wound.

The radial pressure exerted by the gripper on the paper sheet during the winding op eration renders the ends of the convolutions of the sheet flush with each other, so that the ends of the tube are left even and require little or no trimming, the length of the tube being determined mainly by the width of the sheet.

. I claim:

1. In a machine for forming tubes from sheet material, in combination, a rotar nonexpansible mandrel; a gripper of exible resilient sheet material; and gripper-supporting, tensioning and relaxing mechanism organized to movably support the inner end of the gripper relatively near the mandrel and to movably support the outer end of the gripper farther from the mandrel, so that the gripper includes a flexible mandrel-embracing portion and a sheet-guiding portion, tangential to the embracing portion, said mechanism including movable anchoring means engaged with the embracing portion of the gripper, movable tensioning means engaged with the sheet-guiding portion of the gripper and'normally exerting a yielding tension on the grip'per to cause the sheetguiding portion to compress the mandrelembracing portion, and means for relaxing the gripper tension at predetermined periods to permit the expansion of said embracing portion, by the resilience of the material of the gripper.

2. In a machine for forming tubes from sheet material, in combination, a rotary mandrel; a resilient gripper; and gripper-supporting, tensioning and relaxing mechanism organized to movably support the inner end of the gripper relatively near the mandrel and to movably support the outer end of the gripper farther from the mandrel, so that the gripper includes a mandrel-embracing portion and a sheet-guiding portion, said mechanism including a swinging anchoring strut engaged with the inner end of the gripper and fixed means supporting said strut, movable tensioning means engaged with the outer end of the gripper and normally exerting a yielding tension on the gripper to compress itsmandrel-embracing ,portion, and means for relaxing the gripper tension at predetermined periods to permit the expansion of said embracing portion.

3. In a machine for forming tubes from sheet material, in combination, a rotary mandrel; a resilient gripper; and gripper-supporting, tensioning and relaxing mechanism organized to movably support the inner end of the gripper relatively near the mandrel and to movably support the outer end of the gripper farther from the mandrel, so that the gripper includes a mandrel-embracin portion and a sheet-guiding portion, said mechanism including movable anchoring means engaged with the inner end of the gripper, an oscillatory bar engaged with the outer end of the gripper, a fixed support on which said bar is oscillatable, a biasing member adapted to exert a yielding pressure on sion of the gripper and permit the. expansion i of its mandrel-embracing portion.

4. In a machine for forming tubes from sheet material, in combination, a rotary mandrel; a resilient gripper; and grippersupporting, tensioning and relaxing mechanism organized to movably support t e inner end of the gripper relatively ne r the mandrel and to movably support the outer end of the gripper farther from the mandrel, so that the gripper includes a mandrel-embracing portion and a sheet-guiding portion, said mechanism including movable anchoring means engaged with the inner end of the gripper, an oscillatory bar engaged with the outer end of the gripper, a fixed support on which said bar is osciliatable, a biasing member adapted to exert a yielding pressure on the bar to tension the gripper, the bar being provided with lever arms, and variable stop means embodied in collars fixed to a rotary shaft and adapted to alternately maintain the bar in its gripper-tensioning position and displace the bar from said position to permit the expansion of the man drel-embracing portion of the gripper.

In testimony whereof I have affixed my signature.

JOHN D. LANE. 

